Stringed musical instrument



2 SHEETS-SHEET 1 INVENTOR. kfohnfl Cbzwa'neaw,

BY 9 M, *W

J. B. GOUSINEAU STRINGED MUSICAL INSTRUMENT Sept. 16, 1952 Filed Dec. 23, 1949 Patented Sept. 16, 1952 UNITED STATES PATENT OFFICE STRINGED .MUSICAL INSTRUMENT John "B. Cousineau, Forest Park, Ill. Application December 23, 1949, Serial No. 134,803

- '7 Claims.

This invention relates to stringed musical instruments, especially to instruments of the type of the electric steel guitar, and more particularly to an improved tuning mechanism for such instruments.

The utility of the conventional steel guitar, and other similar stringed instruments used with electrical amplification, is seriously limited "by the fact that the strings must be adjusted to a fixed chord tuning which cannot be changed .to any appreciable extent while the instrument is being played. "Thus, with such an instrument there is no satisfactory means of playing chords or partial chords other than those corresponding .to the initial fixed tuning '.of the strings. Obviously, the resultant lack of flexibility and musical range greatly restricts the popularity and adaptability of such instruments especially for use in orchestras and other musical groups.

'Vario'us tuning devices and tuning changers have been suggested for use withinstruments of the foregoing character in order to permit relatively rapid changes in the string tuning. However; such or these devices as have been capable of meeting musical and playing requirements have not been altogether satisfactory 'both for the reason that they'ihave been unduly complicated in structure and operation and also because they are often inaccurate and unreliable in execution of the required changes in tuning. For example,'most of the prior .art devices employ string-tensioning"levers or rollers which are attached to the ends of the playing strings, the opposite ends of the strings being anchored to the instrument whereby the string tension may be'varied by exerting a greater or "lesser pull on the strings longitudinally thereof. Such devices have been found to be unreliable because the levers or rollers which are attached to the ends of the strings tend to "wear or become "misadjusted with the result that "they do not always return to their original positions and thus the initial fixed tuning of the strings is disturbed. In "addition, most'of the prior art string-tensioni-ng devices do not afford "sufi'icient 'fiexlbility'with respect to the number of chord changesthat can be "executed, and those devices that do "permit a substantial number of chord changes are unduly complex in -'construction and 'operation.

Accordingly, a primary object of "my invention is to provide, 'in a stringed musical instrument of the above mentioned type, novel means 'for readrly efiecting frequent and rapid -'changes in the tuning of the strings. 7 Another object of the invention is to "provide,

in a stringed musical instrument of the character described, a tuning mechanism for selectively altering the tension of the strings or predetermined groups thereof which is capable of -a'c'cu-' rate adjustment and which, even with repeated use, does :not tend to disturb the original "fixed tuning of the strings.

A further object of the invention is to provide, in a stringed musical instrument of the character described, 'a novel tuning mechanism having. cooperating means for increasing or decreasing the tension of predetermined combinations pr strings.

An additional object of the invention is 'to'provide, in a stringed musical instrument of the character described, a'novel pedal-operated :tuning mechanism for increasing or decreasing the tension of predetermined combinations of strings by deflecting or relaxing the strings intermediate the anchored ends thereof.

Still another object of my invention is-to provide, in a stringed instrument of the character described, means for selectively varying the ten sion of the strings whereby a 'wide variety of chord changes may be effected.

Other objects-and advantages of the invention will become apparent upon reference to thesn sequent detailed description and the accompanylng drawings, in which:

Fig.1 is a perspective View of an electric steel guitar provided with a tuning changer or stringtensioning device comprising one specific .embodiment of my invention;

Fig. 2 is an enlarged fragmentary plan view of the tuning changer at the right-hand end of the instrument as viewed in Fig. 1;

.Fig. 3 is a transverse sectional view through the tuning changer taken along the line 3-3 :of Fig. .2;

.Fig. 4 is a longitudinal sectional view through the tuning changer taken along the line 4-4 of Fig. 2' and showing parts of the tuning changer thereof.

increasing or decreasing the tension of selected combinations of playing strings. As mentioned above, I have found that it is not satisfactory to control string tension by anchoring the strings at one end and varying the longitudinal pull at the other ends of the strings. Accordingly, in my device string tension is increased by the action of string-deflecting element-s engaging the strings transversely intermediate their opposite ends which are anchored securely in the body of the instrument, and string tension isdecreased by relaxing the strings upon rocking movement of pivotally mounted string supports which engage the strings intermediate the anchored ends My invention also comprises a common operating mechanism, preferably including a pedal bank, for simultaneously increasing or decreasing the tension of selected combinations of strings. Thus, each playing string has three possible pitches corresponding to the normal or initial tension, increased tension, or decreased tensionfand by selecting various combinations of these possible conditions of tension for each string it will be seen that numerous variations of thetuningpattern are made possible.

' iReferringfirst to 'Fig. 1 of the drawings, the invention is illustrated by an electric steel guitar comprising a wood or plastic body II which is provided on its upper surface with'a fingerboard I2 extending longitudinally thereof in the conventional manner. A plurality of playing strings, eight being shown in the'present case as indicated at l3, I4, I5, [6, ll, I3, l9, and 2B, are tensioned along the body of the instrument extending over a nut 2liat one end of the fingerboard l2 and are connected to a plurality of conventional tuning keys 22. The playing strings are anchored at their opposite ends in a tuning changer unit, indicated generally at 23, which is mounted adja'cent the opposite end of the body I i The unit 2'3 comprises a principal feature of the present invention and will be described hereinafter in greater detail.

The body H is supported on a pair of tubular legs 24 having laterally extending base portions 26.. Thertuning changer unit 23 is operated by means of a pedal bank comprisnig a plurality of telescoping rock shafts 28, one for each pedal, extending between the base portions 26. Each of the shafts 28 has secured adjacent one end thereof a rocker arm 29, and a pair of actuating cables 3| extend upwardly from opposite ends of the rocker arm 29 to certain movable portions of the tuning changer unit 23, as hereinafter described.

' The instrument selected for illustration being an electric steel guitar, there is shown in Fig. 1 an electrical pickup device 32 of any well known type which is mounted below the playing strings I3 to 23 and is adapted to transmit the sound vibrations of the strings to an amplifier and loud speaker unit associated with the instrument. The pickup device 32 is provided with suitable volume and tone control means (not shown) which are inserted in the pickup circuit formodifying the volume and tone of the string vibrations. These controls are adapted to be operated manually by means of a pair of control knobs 33 and 33 which are disposed at one side of the instrument and are readily accessible to the hand of the player.

Pursuant to the objects of the present invention, tuning changer or string-tensioning means is provided for selectively varying at will the pitch of predetermined groups of the playing strings I3to 20.. Such variation in-pitch is accomplished 4 by means of the string-tensioning unit 23 which functions independently of the tuning keys 22 and independently of any other string-tensioning mechanism with which an instrument of this type may be equipped.

Referring now to Figs. 2 to 6, the tuning changer or string-tensioning mechanism 23 comprises a substantially rectangular framework or base structure, indicated generally at 35, which is rigidly mounted in an opening'3'l in the body 5 l. The base 36 is provided with a pair of spaced upright parallel sides 38 having a roller shaft 39 extending transversely therebetween at the innermost end of the base 36 with a plurality of grooved string rollers 4i, one for each playing string, rotatably mounted on the shaft 39. An anchor bar 42 (Fig, 2), for purposes hereinafter described, is securedbetween the sides 38 adjacent the rollers ll by means of a pair of screws 13. An end wall or cross member d4 connects the sides 33 at the outer edge of the base 33 and is provided with a plurality of upright bores 43 having tapered or outwardly fiared upper and lower openings, as indicatedat 4'! (Fig. 4) The playing strings E3 to 20 are retained at one end of the instrument by the tuning keys 22 from which they extend along the fingerboard l 2 and over the rollers 45, under the anchor bar 42, through the operating portions of the tuning changer mechanismin an inclined direction as hereinafter described, and finally downwardly into the bores 35 in the end wall 43 where they arefirmly anchored by means of suitable enlarged portions or retainers, such as indicated at 48, afiixed to the opposite ends of the'strings.

For deflecting the playing strings I3 to 2cm order to increase the tension thereof, a plurality of depressible barsAS are supported in parallel side-by-side relation extending transversely across the playing strings between the sides 38 of the base 36. Each of the bars 49 is provided with a series of transverse slots 5| spaced longitudinally of the bar corresponding to the spacing of the playing strings l3 to 20 and extending downwardly into the bar from the upper edge thereof, the slots 5| in each bar 49 being aligned with the corresponding slots in the other bars whereby to provide continuous transverse passageways through which the playing strings l3 to 20 extend. Extending downwardly to the bottom of each of the slots 5| is a threaded bore 52 (Fig. 4) for receiving a string-deflecting element in the form of an adjustable screw 53 adapted to extend to any desired extent into the bore 52 for engaging at its inner end the corresponding playing string upon downward movement of the bar 49. Each of the screws 53 has an enlarged head portion 54 provided with a socket adapted to receive a suitable wrench or tool for effecting rotary adjustment of the screw. A helical spring 55 encircles each of the screws 53 and bears at its opposite ends against the head portion 54 and the top of the bar 49 for stabilizing and retaining the screws 53 in desired adjusted position within the bores 52. It will be understood that not all of the bores 52 in the bars 49 are fitted with screws 53 but instead the number and distribution of the screws 53 are selected to obtain the desired number and type of. chord changes. Thus, as seen in Fig. 2, the device herein illustrated has one bar 49 with no screws 53, four bars with one screw 53 each, one bar with two screws 53, and two bars with three screws 53 each. v

For actuating the bars 49, an elongated reciprocating member in the form of a stem or-pluneer 51. (Figs. 3 and 4) depends centrally. from each bar, the plungers 51 being slidably received in aplurality of bores 58 formed in an inclined bed member 59 secured between the side portions 38 of the base structure 36. The lower ends of the plungers 5'! extend below the bed 59 and each plunger has fastened thereto a separate operating cable 3|. The pedals 21 being tiltable in opposite directions and each rocker arm 29 having two cables secured thereto, it will be seen that only four pedals are needed to operate eight of the bars 49. Each of the bars 49 is provided with a pair of compression springs M (Fig. 3) engaging the bar at its lower face on opposite sides of the plunger 51 and being received in a pair of cavities or recesses 62 on the upper face of the bed 59. As a result of the action of the springs 6|, the bars 49 are normally urged upwardly into elevated or non-deflecting position, upward movement of each of the plungers 51' being limited by means of a cross pin 63 extending diametrically through the plunger 51 below the bore 58 for engagingthe underside of the bed 59. Any desired combination of the bars 49 may be depressed downwardly by rocking the appropriate pedals 21 to eifect downward movement of the corresponding cables 31 attached to the lower ends of the plungers 51. Downward movement of the bars 49 is limited by means of stop members in the'form of a pair of spaced rails 64 (Fig. 3) integral with the bed 59 and extending longitudinally thereof. A pair of spacedpins 66 project upwardly adjacent each end of the bed 59 on opposite sides of the group of bars 49 for loosely retaining the latter in side-by-side relation and for preventing twisting or turning movement of the bars 49 as a result of rotation of the plungers 57 in the bores 58.

It will be seen that upon suitable manipulation of the pedals 21, selected combinations of the-bars 49 may be depressed in order to effect engagement of the screws 53 mounted thereon with any desired group of playing strings l3 to 20, the playing strings thereby being deflected downwardly for increasing the string tension. For example, as seen in Fig. 4, the third bar 49 from the left is shown in depressed condition and the playing string 20 is being deflected downwardly by the screw 53 mounted in the bar. In like manner, the string 20 can also be deflected by depression of the right hand bar 49 orthe third bar from the right as seen in Fig. 4. The bed 59 is disposed within the base structure 36 at an angular or inclined relationship therewith and substantially parallel tothe normal position of the playing strings extending thereabove (Fig. 4) so that the plungers 5'! and the screws 53 are substantially perpendicular to the playing strings.- Thus, the screws 53 always engage the playing strings substantially perpendicularly whereby to effect uniform deflection upon repeated manipulation of the pedals 21 and whereby to avoid any tendency toward slippage of the ends of thescrews 53 along the playing strings.

For relaxing the playing strings l3 to 29 in order to decrease the tension thereof, the tuning changer is provided with a plurality ofpivotally mounted string supports each comprising an upright block or lever 6'! (Figs. 4-6) pivotally or rockably supported on a shaft 68 extending between the sides 38 adjacent the outermost end of the base 39,. A grooved roller 69 is rotatably mounted on a shaft H in a recess or notched portion 12 (Fig. 6) at the top of each of the levers 61. A projection in the form of a retaining pin 13. extends from the bottom of each oithe levers 61 and has secured thereto one end of a tension spring '14 with the other end of the spring 14 being fastened to a cross pin 15 (Fig. 3) extending transversely between the sides 38 and held in place by a pair of pins 76 projecting downwardly from the bed 59. Thus, the tension springs 14 acting, upon the lower end of each of the levers 6! normally retain the levers in upright position with the bottom portion of the levers in abutment against the outer end edge of the bed 59, as seen most clearly at 17 in Fig. 4.

In the normal undeflected position of the playing strings l3; to, 29., each string extends over itsroller'4l and thence inclines downwardly through the aligned slots 5! in the bars 49 and passes over the roller 59 on the corresponding lever 81 and downwardly-to its anchored position in the end wall 44. As hereinafter explained, the levers- 61 are so arranged that under the normal tension;

of the playing strings, the levers are retained in an upright position.

For each of the playing strings [3 to 29 there. is provided an auxiliary string, designated for convenience by the reference numerals I 3a to 29a, the auxiliary strings extending generally parallel to the playing strings and in alternating relationship therewith (Fig. 2) The outer end of each of the auxiliary strings [3a to aextends through a bore (not shown) in the upper end of one of the levers 61 and is anchored by means 'of a retainer T8. The opposite end of each of the auxiliary strings [L to 29a is firmly retained in a suitable aperture (not shown) in the anchor bar 42'by means of a screw 79. The bars 49'are provided with a plurality of aligned slots 5hr, similar to the slots 5i, through which the auxiliary strings l3a to 20a extend in the same man ner as the playing strings I 3 to 29. The slots 5la' are likewise provided with threaded bores'52a, similar to the bores 52 in the slots 5|, for receiving a plurality of deflecting screws 53a having head portions 54a and stabilizing springs 56a (Fig. 3). Upon depression of the appropriate bars 49, it will be understood that selected auxiliary strings are engaged substantially perpendicularly by the string-deflecting screws 53a whereupon the corresponding levers 87- are pivoted or rocked about the shaft 68 against the action of the springs 14 and the associated string-supporting rollers 69 are swung inwardly of the instrument whereby to relax the corresponding playing strings and de-- crease the tension thereof. As in the case of the screws 53, the screws 53d are also distributed in the bores 52a according to any predetermined pattern for obtaining the desired combination of possible chord changes.

In order to permit the use of a plurality of' string deflecting screws 53 and 53a in adjacent positions in any one of the bars 49 withoutinterference between the head portions 54 and 54a, the threaded bores 52 and 52a are staggered in each bar-49 to provide two parallel rows extending longitudinally of the bar (Fig. 2). Thus, the row' of threaded bores 52 receives the screws 53 for deflecting the playing strings 13 to Hand the other row of threaded bores 52a receives the screws 53a'for-defiecting the auxiliary strings 13a to 20a.

Referring now to Fig. 5, one of the levers 61 is shown in solid lines in its normal upright position as retained by'the spring 14 with thepl'aying' string 29 extending downwardly over the roller 69- to its anchored position in the bore 48' in'theend wall 44. Upon downward deflection of the auxiliary string 20a, the lever 61 is rocked to the position shown inbroken lines in Fig. with the result that the playing string is relaxed slightly by the inward movement of its supporting roller 69.

It is an important feature of my invention that the'axis of the roller 69 is positioned above the axis of the pivot shaft 68 and to one side thereof in the direction of the end of the playing string or the outermost end of the tuning changer unit. As a result of this horizontal displacement of the respective axes and the angular relationship of the string extending over the roller 69, as shown in Fig. 5, theresultant or net force of the component tensions existing in the portions of the stringZU on either side of the roller 69 falls substantially along or closely adjacent to the center line, indicated at 8|, connecting the axes of the roller 69 and the pivot shaft 88. The net effect of this arrangement is that in the normal upright position of the lever '61 there is no appreciable force or torque due to the tension of the playing string, tending to effect pivotal movement of the lever inwardly to string-relaxing position, or else the force is so slight that the spring 14 is sufiicient to counteract this torque and retain the lever 67 in upright position.

By correlating the relative angles of the playing string with respect to the center line 8! and the extent of lateral displacement or spacing between the axes of the roller 69 and the pivot shaft 68 to produce this balanced condition, it will be seen that only slight tension need be exerted by the spring id to retain the lever B! in normal upright position. If the pivotal mounting of the lever 61 with respect to the location of the roller E9 and the angular position of the playing string passing over the roller 69 were such that a substantial torque existed tending to rotate the lever to string-relaxing position, it will be seen that a relatively strong spring Hi would be required to insure normal upright positioning of the lever 67. If a relatively strong spring #4 were required, it follows that a greater depressing force by the bars 49 and the screws 53a and, consequently, stronger foot pressure on the pedals 2? would be necessary to effect deflection of the auxiliary strings |3ato 28a thereby seriously diminishing the ease and rapidityof operation of the device.

In Fig. 4, the string 21] is shown in deflected position under increased tension. Because of the above described balanced condition of the lever .61, the increased tension in the string 2! and the resultant decrease in the angle of the long portion of the string to the left of the roller 69, as viewed in Fig. 4, cause the resultant force due to the string tension on opposite sides of the roller to swing counterclockwise toward or beyond the center line 8| connecting the axes ofthe roller 69 and the pivot shaft 63. Thus, direct downward deflection of the playing string 2cdoes', not result in pivotal movement .of the lever 61, but, on the contrary, urges the lever even more strongly to its normal upright position with the lower portion thereof in contact, as at H, with the edge of the bed 59.

Thus, my. invention provides for altering the tension of any of the playing strings 13 to 20 by exerting a localized transverse downward pressure on the same intermediate their anchored or rigidly held ends whereby to increase the tension oi'the strings without rocking the pivotally mounted string-supporting rollers 69. Similarly, the tension of any one of the playing strings I3 to 29 may be decreased by exerting a. downward deflecting pressure on its associated auxiliary strings I3a to 23a whereby to swing the string-supporting roller 69 to a position where the playing string is relaxed and its tension is decreased. Thus, the initial tension of each playing string, as determined by the tuning keys 22, may be either increased or decreased by relatively independent means. By avoiding any change in the positions of the fixed ends of the playing strings during operation of'the tuning changer mechanism, there is no tendency for the initial fixed tuning of the strings to be disturbed. When the bars 49 are restored to normal elevated position after depression thereof, the tensions of the associated playing strings are uniformly restored to their initial values. It will be understood that numerous combinations of tuning patterns may be obtained by means of the tuning changer comprising my invention. For example, by varying the number, distribution, and threaded adjustment of the screws 53 and 53a, difierent combinations or predetermined groups of playing strings 'may be subjected to increased or decreased tension corresponding to the depression of one or more of the bars as by manipulation of the pedals 21. Thus, the nature of my string-tensioning mechanism is such that a wide range of flexibility intuning pattern may be achieved dependent upon the distribution and adjustment of the deflecting screws for both the playing strings and the auxiliary strings. 7 Although the invention has been described in connection with one particular embodiment thereof, it will be understood that various modifications and equivalent structures may be resorted to Without departing from the scope of the invention as defined in the appended claims.

' Iclaim:

1. In a stringed musical instrument having a plurality of playing strings tensioned thereon, means for selectively varying the pitch of said playing strings comprising a plurality of upright levers pivotally mounted adjacent one end of the instrument and having portions of the playing strings tensioned thereover, a plurality of auxiliary strings operatively connected to said levers for efiecting pivotal movement of the latter,-a bed member disposed below said strings and having a plurality of bores therein, a plurality of depressible bars extending transversely across the strings and carrying a plurality of adjustable string-deflecting elements adapted to engage and deflect downwardly a predetermined combination of said playing and auxiliary strings, each of said; bars having a depending plunger disposed for reciprocable movement in one of said cores,- spring means coacting between said bed and said here across said playing and auxiliary strings for engaging and deflecting predetermined combinations thereof 3. In a stringed musical instrument having a plurality of playing strings tensioned thereon, means for selectively'varyin the pitch of said playing strings comprising string-relaxing means operatively associated with each of said playing strings for decreasing the tension thereof, a plurality of auxiliary strings extending generally parallel to said playing strings and operatively connected to said string-relaxing means, a plurality oi depressible bars extending transversely across said playing and auxiliary strings and carrying a plurality of string-deflecting elements for engaging and deflecting predetermined combinations of said playing and auxiliary strings, and operating means for depressing said bars whereby to vary the tension of said predetermined combinations of playing and auxiliary strings.

4. In a stringed musical instrument having a plurality of playing strings tensioned thereon, means for selectively varying the pitch of said playing strings comprising a plurality of levers pivotally mounted adjacent one end of the in strument and havin portions of the playing strings tensioned thereover, the tension of said playing strings being alterable by pivotal movement of said levers, spring means normally retaining said levers in a position corresponding to the initial fixed tension of the playing strings, a plurality of actuating strings attached to said levers and deflectable for effecting pivotal movement of the levers to alter the tension of said playing strings, and means for deflecting a predetermined combina-tion of said actuating strings.

5. In a stringed musical instrument having a plurality of playing strings tensioned thereon, means for selectively varyin the pitch of said playing strings comprising a plurality of upright levers pivotally mounted intermediate their ends, portions of the playing strings being tensioned over the upper portions of said levers, a plurality of springs coacting with the lower ends of said levers and tending to hold said levers against pivotal movement whereby to maintain the playing strings under normal tension, a plurality of auxiliary strings each operatively connected to one of said levers adjacent its upper end for effecting pivotal movement of the levers against the action of said springs upon deflection of the auxiliary strings whereby to decrease the tension of the playing strings extending thereover, and operating means comprising a plurality of stringdefiecting elements adapted to engage and deflect predetermined combinations of said auxiliary strings.

6. In a stringed musical instrument having a plurality of playing strings tensioned thereon, means for selectively varying the pitch of said playing strings comp-rising a supporting structure mounted adjacent one end of the instrument, a plurality of levers pivotally mounted within said structure with portions of the playing strings tensioned thereover, a cross bar mounted on said structure in spaced relation. from said levers, a plurality of auxiliary strings extending parallel to said playing strings each being attached at one end to the upper portion of one of said levers, and anchored at its opposite end to said cross bar, a plurality of adjustable string-deflectin elements disposed above said strings for engaging and deflecting the same, the tension of said playing strings being increased upon direct deflection thereof by said elements and being decreased upon deflection of the auxiliary strings associated therewith, and operating means associated with said string-deflecting elements for deflecting predetermined combinations of said playing and auxiliary strings.

7. In a stringed musical instrument having a plurality of playing strings tensioned thereon, means for selectively varyin the pitch of said playing strings comprising a plurality of upright pivotally mounted levers having rollers mounted adjacent the upper ends thereof above the pivot points of said levers with portions of the playing strings being tensioned over said rollers and extending downwardly to anchored position adiacent one end of the instrument, spring means coacting with said levers for normally retaining said levers in substantially upright position, a plurality of auxiliary strings for said levers each being aflixed at one end to the upper portion of its associated lever for effecting inward pivotal movement of said rollers, a plurality of adjustable string-deflecting elements for engaging and defleeting predetermined combinations of playing and auxiliary strings, the pivot point of each of said levers being spaced slightly from its roller inwardly of the instrument, whereby downward deflection of said playing strings inwardly of said levers tends to hold said levers against pivotal movement.

JOHN B. COUSINEAU.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,458,263 Harlin Jan. 4, 1949 2,468,726 Barr May 3, 1949 

